Increased hexokinase activity, of either ectopic or endogenous origin, protects renal epithelial cells against acute oxidant-induced cell death

J Biol Chem. 2002 Mar 29;277(13):11392-400. doi: 10.1074/jbc.M110927200. Epub 2001 Dec 18.

Abstract

Glucose (Glc) metabolism protects cells against oxidant injury. By virtue of their central position in both Glc uptake and utilization, hexokinases (HKs) are ideally suited to contribute to these effects. Compatible with this hypothesis, endogenous HK activity correlates inversely with injury susceptibility in individual renal cell types. We recently reported that ectopic HK expression mimics the anti-apoptotic effects of growth factors in cultured fibroblasts, but anti-apoptotic roles for HKs have not been examined in other cell types or in a cellular injury model. We therefore evaluated HK overexpression for the ability to mitigate acute oxidant-induced cell death in an established epithelial cell culture injury model. In parallel, we examined salutary heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF) treatment for the ability to 1) increase endogenous HK activity and 2) mimic the protective effects of ectopic HK expression. Both HK overexpression and HB-EGF increased Glc-phosphorylating capacity and metabolism, and these changes were associated with markedly reduced susceptibility to acute oxidant-induced apoptosis. The uniform Glc dependence of these effects suggests an important adaptive role for Glc metabolism, and for HK activity in particular, in the promotion of epithelial cell survival. These findings also support the contention that HKs contribute to the protective effects of growth factors.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenoviridae / genetics
  • Cell Death / drug effects*
  • Cell Line
  • Enzyme Activation
  • Epidermal Growth Factor / metabolism
  • Epithelial Cells / drug effects
  • Epithelial Cells / enzymology
  • Genetic Vectors
  • Glucose / metabolism
  • Heparin-binding EGF-like Growth Factor
  • Hexokinase / metabolism*
  • Humans
  • Hydrogen Peroxide / pharmacology*
  • Intercellular Signaling Peptides and Proteins
  • Kidney Tubules, Proximal / cytology
  • Kidney Tubules, Proximal / drug effects
  • Kidney Tubules, Proximal / enzymology*
  • Oxidants / pharmacology*
  • Phosphorylation

Substances

  • HBEGF protein, human
  • Heparin-binding EGF-like Growth Factor
  • Intercellular Signaling Peptides and Proteins
  • Oxidants
  • Epidermal Growth Factor
  • Hydrogen Peroxide
  • Hexokinase
  • Glucose